I don't believe our alarms are anything but switch based, with the pre 96. OBDII I know allows the option of motion sensor systems and I think it was optional on the 97+ models to have it, can anyone confirm?
If it doesn't have that, then even if you can jumper the system to thinking the doors are on, the alarm will be nearly useless unless someone tries to start the vehicle or pop the hood. The best advice I could give is don't leave anything you don't want stolen or use chain locks/padlocks/etc. And as for the radio, there are some security devices and locks you can get, combined with removing the faceplate(if you have an aftermarket) but otherwise you're pretty much stuck taking the risks.
If they are determined enough and have the time, not even an armored truck is safe from thieves. Food for thought
1995 ZJ ltd, 4.0 i6, *cough stock cough* 253,xxx and still pumping strong
1998 Chevy Cheyenne K1500, 5.7L Vortec, mostly stock
*In peace, sons bury their fathers. In war, fathers bury their sons. - Herodotus
[QUOTE=JasonStebbins]We can call it the Whoosh King Catalog System. :D[/QUOTE]